Just a reminder, no laser night tonight. Have a wonderful labor day!
One of the most powerful tools in debugging circuits is the oscilloscope — it allows you to visualize your analog and digital signals at millisecond or microsecond time scales. This 18 August class at NYC Resistor will teach you basic operation of a handheld oscilloscope: topics include how to setup different time and voltage scales, how to configure the trigger modes to capture fleeting signals and how to use the cursors to measure various qualities of the signals. We’ll also show how to use the ‘scope to trace a signal through a circuit to identify some common problems.
The other most valuable tool in your electrical test equipment toolbox is a multimeter for measuring the instantaneous values of three important electrical measurements: voltage, amperage and resistance. This class covers all three of these as well as the very important “beep mode” to check for electrical connectivity.
Get your tickets here! The class fee includes both a compact multimeter and a DSO Nano v3, an Open Hardware design that is a great getting started oscilloscope. With these in your toolbox you’ll be able to diagnose all manners of circuit issues.
Are you building a giant LED display for your hackerspace or Burning Man and need a way to control multiple kilometers of LED strips? Are you tired of running massive USB hubs of Teensys for each row? Then you might be interested in my LEDscape code for the BeagleBone Black to drive up to 500 meters of WS2811 RGB LED strips at 30fps.
On the Teensy 3, Paul’s OctoWS2811 makes very clever use of three DMA engines to generate the bit-train for the WS2811 LED strips, but only supports up to eight strips. Beth’s FadeCandy improves on Paul’s work and has a great frame rate with beautiful interpolation (and a custom USB protocol to pump pixels fast enough to keep up with the frame rate), but the temporal dithering and expanded colorspace features run into frame rate and memory limitations at strips beyond 64 pixels.
The BeagleBone Black has far more memory than the embedded AVRs (512MB versus 16KB) and the AM335x ARM Cortex-A8 has a killer feature: two built in PRU (“Programmable Realtime Units”). These are embedded real-time microcontrollers built into the ARM core with full DMA to main memory and control over all of the IO pins. This afternoon I hacked up a quick proof of concept in PRU assembly that use one of the units to drive 32 of the WS2811 strips at full speed with zero CPU load and easy double-buffering of the image. The best parts of writing for the ARM instead of the AVR is that there aren’t any issues with running out of memory for image processing and there is built-in ethernet for OSC or other visualization libraries.
Last month I went to Paris with a bunch of artists to work on an installation at the Palais de Tokyo museum. The structure in the picture is made mostly from salvaged materials, and it’s full of robotic musical instruments and noisemakers – all controlled through MIDI, the 30 year old protocol that will never die. Here’s a nice virtual tour of the thing.
This is a project I made for my two year old nephew. He really likes bright lights and buttons, so I wanted to make something special for him with plenty of both. I made it from a clear box so he could see the parts inside. As he’s a curious boy, I wanted this to spark a lifelong curiosity about how things work.
Since this toy is fully programmable, it can evolve as he gets older. The behavior now is simple: change light colors and patterns based on the knob state and button presses. Once he’s a little older, I can reprogram this to be a memory game where he has to reproduce certain patterns. If it survives early childhood, perhaps I can even teach him to program it himself…
Join us this Saturday, June 29 1-4pm, for this month’s installment of our Make-Along series!
Make-Along–A Monthly Crafting Event at NYCR
This is not your typical craft class. Make-Along is a self-guided craft workshop where participants learn new skills, explore new materials, and make great things!
This Month’s Topic: Stuffed Toys!
In this session we’ll be exploring the wonderful world of plushies, amigurumi, and other stuffed toys, including ones specifically made for the tiniest of makers. A perfect session to make a gift for all your baby-expecting friends or to make yourself a squishy new BFF to clutch while you nervously watch GAME OF THRONES. (For the record Grumpy Cat is NOT impressed with that show.)
Are you a beginner? We’ll provide materials for a variety of projects and will help you learn to use a sewing machine, hand-stitch, crochet, and will help guide you through anything else your project requires.
Are you a master? Show off your skills and inspire others! Bring a project, use our materials, and hang out in a great space while doing what you love!
Looking for project ideas? Check out our Pinterest board.
Last month we introduced Future Crew, and at the 2013 Interactive Show we finally unveiled the
fully mostly operational game stations. There were five stations in the final design, and in keeping with the show’s “Digital Archaeology” theme, each was built from repurposed ancient hardware. The brains of each console was a Raspberry Pi (to connect to the network and draw OpenGL graphics) and some number of Teensy microcontrollers to interface with the real world. Of course, the source is available for you to build your own Future Crew stations!
A discarded video edit console and RF TV became the Timeline controller. Since the Pi can turn the composite video on-and-off, one of the modes glitches out the TV occasionally with real static! This one had some of the more imaginative tasks like “disable all blinking buttons” in addition to the normal tasks like “advance the timeline!”.
A rackmount data acquisition analog-digital converter and three NTSC TVs became the Blender control unit and Technobabble patch panel. The labels were printed on our large format plotter and then the BNC holes were cut on the laser cutter. The teensy++ firmware can handle arbitrary cross connects and even multi-way connections. This was one of the harder stations to play — there are eight switches, twenty verbs and twenty nouns. We ended up disabling all the verbs except “MODULATE” since it was much too difficult to find the right ones. As a todo item we plan to ramp up the difficulty as the game goes on.
A 1930′s Model 15 Teletype and some random video switcher served as the slowest output console. It’s amazing that the teletype functioned nearly perfectly for the entire eight hour show — perhaps the fresh quart of oil during the previous servicing helped keep it working. The source for this console is one of the simpler ones — it just prints to a file descriptor to write to the teletype.
One of the hardest consoles was made from a toy piano. Even with the song book, playing “Row Row Row Your Boat” under duress is not easy.
And a last minute entry was a rotary phone. Quick! Get the President on the line! This time the handset just had a recorded loop, but future games will incorporate text to speech.
We have a whole list of things to fix and improvements to make before Makerfaire 2013. Stop by NYCR to play it during Craft Night on Thursdays and give us your suggestions!
Take that Babbage! A *working* mechanical computer. That’s right, I said it. Come check out the Turbo Entabulator at the upcoming NYCResistor Interactive Show this coming Saturday! This is the latest diabolical machine to come out of the labs at Fenton Heavy Industries. Its lack of speed is only surpassed by its unreliability and general mechanical shakiness. But hey, it’s probably the only computer you can print out yourself.
Cathode ray oscillographs weren’t just used for reading tweets in the 1940′s, they were also used as vector displays for serious astronomical simulations and training systems like “Space Rocks”. You can play it at the 2013 NYC Resistor Interactive Show!
While the Delta-V of the simulator space craft was optimistic for its era, the basic acceleration, velocity and position model is reasonably accurate. If the ship passes too closely to one of the space rocks, it is destroyed and the simulation restarts. Once the ship runs out of fuel (measured in hexadecimal in the upper left corner since the CPU can’t perform a DIV/MOD operation fast enough to display decimal numbers), it is stranded and unable to continue its mission.
We were not able to locate an original controller, but the interface is similar enough to more modern analog joysticks that we could wire it in. Have your own vector display? spacerocks.c is the source for the Teensy to drive it.